/**
 * Copyright (C) 2008 Google Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.google.inject.internal;

import static com.google.common.base.Preconditions.checkNotNull;

import com.google.common.collect.ImmutableList;
import com.google.common.collect.ImmutableMap;
import com.google.common.collect.Lists;
import com.google.common.collect.Maps;
import com.google.inject.Binding;
import com.google.inject.Key;
import com.google.inject.Scope;
import com.google.inject.TypeLiteral;
import com.google.inject.spi.ModuleAnnotatedMethodScannerBinding;
import com.google.inject.spi.ProvisionListenerBinding;
import com.google.inject.spi.ScopeBinding;
import com.google.inject.spi.TypeConverterBinding;
import com.google.inject.spi.TypeListenerBinding;

import java.lang.annotation.Annotation;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.Map;
import java.util.Set;

/**
 * @author jessewilson@google.com (Jesse Wilson)
 */
final class InheritingState implements State {

    private final State parent;

    // Must be a linked hashmap in order to preserve order of bindings in Modules.
    private final Map<Key<?>, Binding<?>> explicitBindingsMutable = Maps.newLinkedHashMap();
    private final Map<Key<?>, Binding<?>> explicitBindings = Collections.unmodifiableMap(explicitBindingsMutable);
    private final Map<Class<? extends Annotation>, ScopeBinding> scopes = Maps.newHashMap();
    private final List<TypeConverterBinding> converters = Lists.newArrayList();
    /*if[AOP]*/
    private final List<MethodAspect> methodAspects = Lists.newArrayList();
    /*end[AOP]*/
    private final List<TypeListenerBinding> typeListenerBindings = Lists.newArrayList();
    private final List<ProvisionListenerBinding> provisionListenerBindings = Lists.newArrayList();
    private final List<ModuleAnnotatedMethodScannerBinding> scannerBindings = Lists.newArrayList();
    private final WeakKeySet blacklistedKeys;
    private final Object lock;

    InheritingState(State parent) {
        this.parent = checkNotNull(parent, "parent");
        this.lock = (parent == State.NONE) ? this : parent.lock();
        this.blacklistedKeys = new WeakKeySet(lock);
    }

    public State parent() {
        return parent;
    }

    @SuppressWarnings("unchecked") // we only put in BindingImpls that match their key types
    public <T> BindingImpl<T> getExplicitBinding(Key<T> key) {
        Binding<?> binding = explicitBindings.get(key);
        return binding != null ? (BindingImpl<T>) binding : parent.getExplicitBinding(key);
    }

    public Map<Key<?>, Binding<?>> getExplicitBindingsThisLevel() {
        return explicitBindings;
    }

    public void putBinding(Key<?> key, BindingImpl<?> binding) {
        explicitBindingsMutable.put(key, binding);
    }

    public ScopeBinding getScopeBinding(Class<? extends Annotation> annotationType) {
        ScopeBinding scopeBinding = scopes.get(annotationType);
        return scopeBinding != null ? scopeBinding : parent.getScopeBinding(annotationType);
    }

    public void putScopeBinding(Class<? extends Annotation> annotationType, ScopeBinding scope) {
        scopes.put(annotationType, scope);
    }

    public Iterable<TypeConverterBinding> getConvertersThisLevel() {
        return converters;
    }

    public void addConverter(TypeConverterBinding typeConverterBinding) {
        converters.add(typeConverterBinding);
    }

    public TypeConverterBinding getConverter(String stringValue, TypeLiteral<?> type, Errors errors, Object source) {
        TypeConverterBinding matchingConverter = null;
        for (State s = this; s != State.NONE; s = s.parent()) {
            for (TypeConverterBinding converter : s.getConvertersThisLevel()) {
                if (converter.getTypeMatcher().matches(type)) {
                    if (matchingConverter != null) {
                        errors.ambiguousTypeConversion(stringValue, source, type, matchingConverter, converter);
                    }
                    matchingConverter = converter;
                }
            }
        }
        return matchingConverter;
    }

    /*if[AOP]*/
    public void addMethodAspect(MethodAspect methodAspect) {
        methodAspects.add(methodAspect);
    }

    public ImmutableList<MethodAspect> getMethodAspects() {
        return new ImmutableList.Builder<MethodAspect>().addAll(parent.getMethodAspects()).addAll(methodAspects).build();
    }
    /*end[AOP]*/

    public void addTypeListener(TypeListenerBinding listenerBinding) {
        typeListenerBindings.add(listenerBinding);
    }

    public List<TypeListenerBinding> getTypeListenerBindings() {
        List<TypeListenerBinding> parentBindings = parent.getTypeListenerBindings();
        List<TypeListenerBinding> result = Lists.newArrayListWithCapacity(parentBindings.size() + typeListenerBindings.size());
        result.addAll(parentBindings);
        result.addAll(typeListenerBindings);
        return result;
    }

    public void addProvisionListener(ProvisionListenerBinding listenerBinding) {
        provisionListenerBindings.add(listenerBinding);
    }

    public List<ProvisionListenerBinding> getProvisionListenerBindings() {
        List<ProvisionListenerBinding> parentBindings = parent.getProvisionListenerBindings();
        List<ProvisionListenerBinding> result = Lists.newArrayListWithCapacity(parentBindings.size() + provisionListenerBindings.size());
        result.addAll(parentBindings);
        result.addAll(provisionListenerBindings);
        return result;
    }

    public void addScanner(ModuleAnnotatedMethodScannerBinding scanner) {
        scannerBindings.add(scanner);
    }

    public List<ModuleAnnotatedMethodScannerBinding> getScannerBindings() {
        List<ModuleAnnotatedMethodScannerBinding> parentBindings = parent.getScannerBindings();
        List<ModuleAnnotatedMethodScannerBinding> result = Lists.newArrayListWithCapacity(parentBindings.size() + scannerBindings.size());
        result.addAll(parentBindings);
        result.addAll(scannerBindings);
        return result;
    }

    public void blacklist(Key<?> key, State state, Object source) {
        parent.blacklist(key, state, source);
        blacklistedKeys.add(key, state, source);
    }

    public boolean isBlacklisted(Key<?> key) {
        return blacklistedKeys.contains(key);
    }

    public Set<Object> getSourcesForBlacklistedKey(Key<?> key) {
        return blacklistedKeys.getSources(key);
    }

    public Object lock() {
        return lock;
    }

    public Map<Class<? extends Annotation>, Scope> getScopes() {
        ImmutableMap.Builder<Class<? extends Annotation>, Scope> builder = ImmutableMap.builder();
        for (Map.Entry<Class<? extends Annotation>, ScopeBinding> entry : scopes.entrySet()) {
            builder.put(entry.getKey(), entry.getValue().getScope());
        }
        return builder.build();
    }
}
